The invention relates to a software damper and to a method for configuring a software damper connected to a clutch control system for damping chatter vibrations of a clutch torque being transferred by means of an automated friction clutch positioned between a combustion engine and a transmission and controlled by the clutch control system, wherein a transmission input speed is captured at the output of the friction clutch by means of the software damper, and the target clutch torque encumbered by chatter vibrations is corrected by means of negative feedback.
Automated friction clutches, for example friction clutches combined into a dual clutch, are sufficiently well known and are inserted into drivetrains having a combustion engine and a transmission, for example an automated shift transmission, dual-clutch transmission or the like, between the combustion engine and the transmission. In such cases, the friction clutch is operated by means of a clutch positioner as well as a clutch actuator. The clutch actuator is controlled by a clutch control system. The clutch control system contains a regulator that operates the friction clutch on the basis of a target clutch torque which can be obtained by means of a driving strategy program depending, for example, on a driver's desired torque, driving situations, road conditions and the like, in such a way that a specified clutch torque is present at its output.
Because of the properties of the friction clutch, the transmission and the like, chatter processes may occur at the friction clutch which result in a vibration-accompanied transfer of the target clutch torque with a fixed frequency response in a frequency range up to 30 Hz, for example.
In order to damp this frequency response, a method for reducing chatter vibrations is known from DE 10 2013 204 698 A1, in which an emulated vibration absorber, i.e., a software-based vibration absorber, is superimposed on the clutch positioner for the target clutch torque as a software damper.